Microwave assistant synthesis, antifungal activity and DFT theoretical study of some novel 1,2,4-triazole derivatives containing pyridine moiety

Synthesis, density functional theory and kinetic studies of aminopyridine based α-glucosidase inhibitors

Aims: The current study aimed to develop new thiourea derivatives as potential α-glucosidase inhibitors for the management of hyperglycemia in patients of Type 2 diabetes, with a focus on identifying safer and more effective antidiabetic agents. Materials & methods: New thiourea derivatives (1-16) were synthesized through single-step chemical transformation and evaluated for in vitro α-glucosidase inhibition. Kinetic studies identified the mode of inhibition, free energy and type of interactions were analyzed through density functional theory and molecular docking. Results & conclusion: Compound 5 was identified as the most potent, noncompetitive and noncytotoxic inhibitor of α-glucosidase enzyme with a half-maximal inhibitory concentration of 24.62 ± 0.94 μM. Computational studies reinforce experimental results, demonstrating significant enzyme interactions via hydrophobic and π-π stacking forces.

Synthesis, antimicrobial activity and modeling studies of thiazoles bearing pyridyl and triazolyl scaffolds

In this study, novel 4-(5-((2/3/4-substituted benzyl)thio)-4-(4-substituted phenyl)-4H-1,2,4-triazol-3-yl)-2-(pyridin-3/4-yl)thiazoles were synthesized following a multi-step synthetic procedure. All the compounds were screened with a panel of gram positive/negative bacteria, yeasts, and molds for antimicrobial activity using the disc diffusion method. Then, the minimum inhibitor concentration (MIC) and the minimum bactericidal concentration (MBC) values of active compounds were determined against Micrococcus luteus, Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus using the broth microdilution technique. These compounds were also screened for their inhibitory activities against S. aureus DNA gyrase by supercoiling assay. Furthermore, the crystal structure of S. aureus DNA gyrase B ATPase was subjected to a docking experiment to identify the possible interactions between the most active ligand and the active site. Lastly, the in silico technique was performed to analyze and predict the drug-likeness, molecular and ADME properties of the synthesized molecules.

Crystal structure of 2-((4-phenyl-5-(pyridin-4-yl)-4H-1,2,4-triazol-3-yl)thio)acetonitrile, C15H11N5S

C15H11N5S, orthorhombic, Pbca (no. 61), a = 9.7864(2) Å, b = 15.5709(3) Å, c = 18.7774(4) Å, V = 2861.36(10) Å3, Z = 8, R gt (F) = 0.0485, wR ref (F 2) = 0.1390, T = 296.15 K.

Mono-Alkylated Ligands Based on Pyrazole and Triazole Derivatives Tested Against Fusarium oxysporum f. sp. albedinis: Synthesis, Characterization, DFT, and Phytase Binding Site Identification Using Blind Docking/Virtual Screening for Potent Fophy Inhibitors

Twelve recent compounds, incorporating several heterocyclic moieties such as pyrazole, thiazole, triazole, and benzotriazole, made in excellent yield up to 37–99.6%. They were tested against Fusarium oxysporum f. sp. albedinis fungi (Bayoud disease), where the best results are for compounds 2, 4, and 5 with IC₅₀ = 18.8–54.4 μg/mL. Density functional theory (DFT) study presented their molecular reactivity, while the docking simulations to describe the synergies between the trained compounds of dataset containing all the tested compounds (57 molecules) and F. oxysporum phytase domain (Fophy) enzyme as biological target. By comparing the results of the docking studies for the Fophy protein, it is found that compound 5 has the best affinity followed by compounds 2 and 4, so there is good agreement with the experimental results where their IC₅₀ values are in the following order: 74.28 (5) < 150 (2) < 214.10 (4), using Blind docking/virtual screening of the homology modeled protein and two different tools as Autodock Vina and Dockthor web tool that gave us predicted sites for further antifungal drug design.

Effect of treatment with silver(I) complex of metronidazole on ocular rosacea: Design and formulation of new silver drug with potent antimicrobial activity

BACKGROUND

Metronidazole with well-soluble silver nitrate forms a complex with potent activity (synergism) against bacterial strains and fungi with simultaneous lower side effect than in the case of the two agents administered separately. This study aimed to establish effectiveness in the treatment of ocular rosacea with new formulation of drops and ointment with silver(I) complex of metronidazole.

METHODS

Three patients suffering from serious ophthalmic complications of acne rosacea were treated with drops and ointments applied 3 times a day for 3 months. The uncorrected visual acuity testing (UCVA), pachymetry as well as subjective and objective tear film assessment were evaluated.

RESULTS

In all patients, we have improved UCVA as well as objective and subjective evaluation of the tear film parameters. No significant differences in corneal thickness were observed.

CONCLUSION

Well soluble silver(I) complex of metronidazole might be an alternative method in ophthalmic complications of acne rosacea treatment.

Exploring the Chemistry and Therapeutic Potential of Triazoles: A Comprehensive Literature Review

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Triazole is a valuable platform in medicinal chemistry, possessing assorted pharmacological properties, which could play a major role in the common mechanisms associated with various disorders like cancer, infections, inflammation, convulsions, oxidative stress and neurodegeneration. Structural modification of this scaffold could be helpful in the generation of new therapeutically useful agents. Although research endeavors are moving towards the growth of synthetic analogs of triazole, there is still a lot of scope to achieve drug discovery break-through in this area. Upcoming therapeutic prospective of this moiety has captured the attention of medicinal chemists to synthesize novel triazole derivatives. The authors amalgamated the chemistry, synthetic strategies and detailed pharmacological activities of the triazole nucleus in the present review. Information regarding the marketed triazole derivatives has also been incorporated. The objective of the review is to provide insights to designing and synthesizing novel triazole derivatives with advanced and unexplored pharmacological implications.

Silver(I) Complexes of the Pharmaceutical Agents Metronidazole and 4-Hydroxymethylpyridine: Comparison of Cytotoxic Profile for Potential Clinical Application

In previous papers, we have reported on the high antifungal and significant antibacterial activity against Gram-positive and Gram-negative bacteria of the water-soluble silver(I) complexes of metronidazole and derivatives of pyridine compared to silver nitrate. In the present study, the cytotoxic activity of the silver(I) complexes of metronidazole and 4-hydroxymethylpyridine was compared with that of silver nitrate. Metronidazole and 4-hydroxymethylpyridine were investigated using Balb/c 3T3 and HepG2 cell lines in order to evaluate the potential clinical application of silver(I) complexes. The cells were exposed for 72 h to compounds at eight concentrations. The cytotoxic concentrations (IC₅₀) of the study compounds were assessed within four biochemical endpoints: mitochondrial activity, lysosomal activity, cellular membrane integrity, and total protein content. The investigated silver(I) complexes displayed comparable cytotoxicity to that of silver nitrate used in clinics. Mean cytotoxic concentrations calculated for investigated silver(I) complexes from concentration-response curves ranged from 2.13 to 26.5 µM. HepG2 cells were less sensitive to the tested complexes compared to fibroblasts (Balb/c 3T3). However, the most affected endpoint for HepG2 cells was cellular membrane damage. The cytotoxicity of both silver complexes was comparable for Balb/c 3T3 cells. The cytotoxic potential of the new silver(I) compounds compared to that of silver nitrate used in medicine indicates that they are safe and could be used in clinical practice. The presented results are yet more stimulating to further studies that evaluate the therapeutic use of silver complexes.

Design, Synthesis, and Biological Activities of Novel Pyrazole Oxime Compounds Containing a Substituted Pyridyl Moiety

In this paper, in order to find novel biologically active pyrazole oximes, a series of pyrazole oxime compounds bearing a substituted pyridyl unit were prepared. Bioassays showed that some target compounds were found to have good acaricidal activity against Tetranychus cinnabarinus at a concentration of 500 μg/mL, compound 9q especially displayed potent acaricidal activity against T. cinnabarinus when the concentration was reduced to 100 μg/mL. Interestingly, most target compounds possessed excellent insecticidal activities against Oriental armyworm at 500 μg/mL. Moreover, some compounds were active against Aphis medicaginis and Nilaparvata lugens at 500 μg/mL. Additionally, compounds 9b, 9g, 9l, 9p, 9q, 9r, 9s, 9t, 9u, and 9v displayed significant antiproliferative activities against HepG2 cells with IC₅₀ values of 1.53-17.27 μM, better than that of the control 5-fluorouracil (IC₅₀ = 35.67 μM).

Crystal structure of 4-(5-((2-methylbenzyl)thio)-4-phenyl-4H-1,2,4-triazol-3-yl)pyridine, C21H18N4S

C21H18N4S, monoclinic, P21/c (no. 14), a = 18.264(2) Å, b = 11.6302(14) Å, c = 8.9289(10) Å, β = 101.683(7)°, V = 1857.3(4) Å3, Z = 4, R gt (F) = 0.0435, wR ref(F2 ) = 0.1122, T = 296(2) K.

Crystal structure of 2-(5-(4-fluorophenyl)-3-p-tolyl-4,5-dihydro-1H-pyrazol-1-yl)-4-(5-methyl-1-p-tolyl-1H-1,2,3-triazol-4-yl)thiazole, C29H25FN6S

C29H25FN6S, triclinic, P1̅, a = 7.5726(8) Å, b = 11.1428(13) Å, c = 16.412(2) Å, α = 91.823(5)°, β = 102.277(5)°, γ = 106.692(4)°, V = 1289.8(3) Å3, Z = 2, Rgt(F) = 0.079, wRref(F2) = 0.205, T = 296 K.

Crystal structure of 5-methoxy-4-methyl-2-(2-methylbenzyl)-2,4-dihydro-3H-1,2,4-triazol-3-one, C12H15N3O2

C12H15N3O2, monoclinic, P21/c, a = 10.480(3) Å, b = 14.608(4) Å, c = 8.3398(17) Å, β = 106.753(18)°, V = 1222.6(5) Å3, Z = 4, R gt (F) = 0.0700, wR ref(F2 ) = 0.1896, T = 296(2) K.

Antibacterial Activity and Cytotoxicity of Silver(I) Complexes of Pyridine and (Benz)Imidazole Derivatives. X-ray Crystal Structure of [Ag(2,6-di(CH2OH)py)2]NO3

Selected aspects of the biological activity of a series of six nitrate silver(I) complexes with pyridine and (benz)imidazole derivatives were investigated. The present study evaluated the antibacterial activities of the complexes against three Gram-negative strains: Pseudomonas aeruginosa ATCC 15442, Escherichia coli ATCC 25922 and Proteus hauseri ATCC 13315. The results were compared with those of silver nitrate, a silver sulfadiazine drug and appropriate ligands. The most significant antibacterial properties were exerted by silver(I) complexes containing benzimidazole derivatives. The cytotoxic activity of the complexes was examined against B16 (murine melanoma) and 10T1/2 (murine fibroblasts) cells. All of the tested silver(I) compounds were not toxic to fibroblast cells in concentration inhibited cancer cell (B16) viability by 50%, which ranged between 2.44–28.65 µM. The molecular and crystal structure of silver(I) complex of 2,6-di(hydroxymethyl)pyridine was determined by single-crystal X-ray diffraction analysis. The most important features of the crystal packing and intermolecular non-covalent interactions in the Ag(I) complex were quantified via Hirshfeld surface analysis.

A Facile One-Pot Synthesis of Novel 1,2,4-Triazolo[4,3-a]Pyridine Derivatives Containing the Trifluoromethyl Moiety Using Microwave Irradiation

A series of novel substituted 8-chloro-6-(trifluoromethyl)-[1,2,4]triazolo[4,3-a]pyridines are synthesised from 2,3-dichloro-5-(trifluoromethyl)pyridine, hydrazine hydrate as starting materials by multi-step reactions under microwave irradiation. Their chemical structures can be characterised by 1H NMR, MS and elemental analysis. The title compounds exhibit weak antifungal activity.

Microwave assisted synthesis, antifungal activity, and DFT study of some novel triazolinone derivatives

A series of some novel 1,2,4-triazol-5(4H)-one derivatives were designed and synthesized under microwave irradiation via multistep reaction. The structures of 1,2,4-triazoles were confirmed by ¹H NMR, MS, FTIR, and elemental analysis. The antifungal activities of 1,2,4-triazoles were determined. The antifungal activity results indicated that the compounds 5c, 5f, and 5h exhibited good activity against Pythium ultimum, and the compounds 5b and 5c displayed good activity against Corynespora cassiicola. Theoretical calculation of the compound 5c was carried out with B3LYP/6-31G (d). The full geometry optimization was carried out using 6-31G(d) basis set, and the frontier orbital energy and electrostatic potential were discussed, and the structure-activity relationship was also studied.

SiO2–H3BO3 promoted solvent-free, green and sustainable synthesis of bioactive 1-substituted-1H-tetrazole analogues

Eco-friendly and expeditious synthesis of tetrazole derivatives.

Synthesis, insecticidal activity, structure–activity relationship (SAR) and density functional theory (DFT) of novel anthranilic diamides analogs containing 1,3,4-oxadiazole rings

A series of anthranilic diamides analogs (5a–x) containing 1,3,4-oxadiazole rings were synthesized, and their insecticidal activities were evaluated. The density functional theory (DFT) studies was used to understand the various insecticidal activities.